EJB deployment inWebsphere 3.5 Advanced edition

I will deploy entity bean in websphere davanced edition 3.5
I becam the flowing error:
java.lang.ClassNotFoundException: COM.ibm.db2.jdbc.DB2XADataSourcejava.sql.SQLException:
java.lang.ClassNotFoundException: COM.ibm.db2.jdbc.DB2XADataSource
--------
com.ibm.ejs.sm.client.command.ExecutionException: Fehler beim Unterbefehl des Befehls 'myEJBContainer.start'.
at com.ibm.ejs.sm.client.RepositoryOpException.<init>(RepositoryOpException.java:51)
at com.ibm.ejs.sm.client.command.ExecutionException.<init>(ExecutionException.java:63)
at com.ibm.ejs.sm.client.command.AbstractCommand.handleAct(AbstractCommand.java(Compiled Code))
at com.ibm.ejs.sm.client.command.StartCommand.execute(StartCommand.java:93)
at com.ibm.ejs.sm.client.command.CommandManager$ExecutionThread.run(CommandManager.java:264)
at com.ibm.ejs.sm.client.command.ThreadPool$PooledThread.run(ThreadPool.java(Compiled Code))

I tested servlet with the same Driver and it functioned , so the classpfad is already set .
can someone help me